The invention relates to a medical instrument having a hollow shank and an instrument section including an instrument part movably mounted in the instrument section, wherein the instrument section is arranged close to the distal end of the hollow shank and in a pivotable manner to the hollow shank,
Hollow-shank instruments, such as manipulators, forceps or scissors are known for endoscopic application, with which movable instrument parts arranged at the distal end of a hollow shank are coupled in movement via an actuation element, which is axially movably guided in the hollow shank, to a handle arranged at the proximal end of the hollow shank, and thus may be operated. Instruments have been developed which, distally of the hollow shank, comprise an end piece, which is pivotable relative to the straight hollow shank in order, via an access channel into the inside of a body, to also be able to reach those treatment regions which lie laterally of an access axis defined by the access channel. However, with these instruments, and with a pivoted (angled) end piece, the force transmission from the handle to the movable instrument part on the pivotable end piece has been found to be problematic, since only relatively small forces may be transmitted by an actuation element in the hollow shank to the movable instrument part.
It is known to use control wires, which are typically fastened on the end piece distally spaced from a pivot axis of this end piece and which are led through the hollow shank to the proximal-end handle for actuation, for pivoting the pivotable distal end piece of these instruments. The pivoting ability of the end-piece is limited, however, due to the fact that the control wires, which bend transversely to their longitudinal axis with the pivoting of the end-piece, may not be bent up to a kinking limit, since the end-piece may no longer be pivoted back if the control wire is kinked. Insofar as this is concerned, the end-pieces of these instruments may only be pivoted within a comparatively small angular range.